Garcinol, a multifaceted sword for the treatment of Parkinson's disease

A critical appraisal on the involvement of plant-based extracts as neuroprotective agents (2012-2022): an effort to ease out decision-making process for researchers

The purpose of this review study is to provide a condensed compilation of 164 medicinal plants that have been investigated for their neuroprotective aspects by researchers between the years 2012 and 2022 which also includes a recent update of 2023-2024. After using certain keywords to retrieve the data from SCOPUS, it was manually sorted to eliminate any instances of duplication. The article is streamlined into three major segments. The first segment takes a dig into the current global trend and attempts to decrypt vital information related to plant names, families, plant parts used, and neurological disorders investigated. The second segment of the article makes an attempt to present a comprehensive insight into the various mechanistic pathways through which phytochemicals can intervene to exert neuroprotection. The final segment of the manuscript is a bibliometric appraisal of all researches conducted. The study is based on 256 handpicked articles based on decided inclusion criteria. Illustrative compilation of various pathways citing their activation and deactivation channels are also presented with possible hitting points of various phytochemicals. The present study employed Microsoft Excel 2019 and VOS viewer as data visualisation tools.

Garcinol prevents oxidative stress-induced bone loss and dysfunction of BMSCs through NRF2-antioxidant signaling

There are multiple published data showing that excessive oxidative stress contributes to bone loss and even bone tissue damage, and it is also correlated with the pathophysiology of bone degenerative diseases, including osteoporosis (OP). Garcinol, a polyisoprenylated benzophenone derivative, has been recently established as an anti-oxidant agent. However, it remains elusive whether Garcinol protects bone marrow mesenchymal stem cells (BMSCs) and bone tissue from oxidative stress-induced damage. Here, we explored the potential effects of Garcinol supplementation in ameliorating oxidative stimulation-induced dysfunction of BMSCs and bone loss in osteoporotic mice. In this study, we verified that Garcinol exerted potent protective functions in the hydrogen peroxide (H2O2)-induced excessive oxidative stress and dysfunction of BMSCs. Besides, Garcinol was also identified to improve the reduced bone mass and abnormal lineage commitment of BMSCs in the condition of OP by suppressing the oxidative stimulation. Subsequent analysis revealed that nuclear factor erythroid 2-related factor 2 (NRF2) might be a key regulator in the sheltering effects of Garcinol on the H2O2-regulated oxidative stress, and the protective functions of Garcinol was mediated by NRF2-antioxidant signaling. Collectively, Garcinol prevented oxidative stress-related BMSC damage and bone loss through the NRF2-antioxidant signaling, which suggested the promising therapeutic values of Garcinol in the treatment of oxidative stress-related bone loss. Therefore, Garcinol might contribute to treating OP.

Advances in the Delivery and Development of Epigenetic Therapeutics for the Treatment of Cancer

Gene expression at the transcriptional level is altered by epigenetic modifications such as DNA methylation, histone methylation, and acetylation, which can upregulate, downregulate, or entirely silence genes. Pathological dysregulation of epigenetic processes can result in the development of cancer, neurological problems, metabolic disorders, and cardiovascular diseases. It is of promising therapeutic interest to find medications that target these epigenetic alterations. Despite the enormous amount of work that has been done in this area, very few molecules have been approved for clinical purposes. This article provides a comprehensive review of recent advances in epigenetic therapeutics for cancer, with a specific focus on emerging delivery and development strategies. Various delivery systems, including pro-drugs, conjugated molecules, nanoparticles (NPs), and liposomes, as well as remedial strategies such as combination therapies, and epigenetic editing, are being investigated to improve the efficacy and specificity of epigenetic drugs (epi-drugs). Furthermore, the challenges associated with available epi-drugs and the limitations of their translation into clinics have been discussed. Target selection, isoform selectivity, physiochemical properties of synthesized molecules, drug screening, and scalability of epi-drugs from preclinical to clinical fields are the major shortcomings that are addressed. This Review discusses novel strategies for the identification of new biomarkers, exploration of the medicinal chemistry of epigenetic modifiers, optimization of the dosage regimen, and design of proper clinical trials that will lead to better utilization of epigenetic modifiers over conventional therapies. The integration of these approaches holds great potential for improving the efficacy and precision of epigenetic treatments, ultimately benefiting cancer patients.

Garcinia kola: a critical review on chemistry and pharmacology of an important West African medicinal plant

Garcinia kola Heckel (Clusiaceae) is a tree indigenous to West and Central Africa. All plant parts, but especially the seeds, are of value in local folklore medicine. Garcinia kola is used in treatment of numerous diseases, including gastric disorders, bronchial diseases, fever, malaria and is used to induce a stimulating and aphrodisiac effect. The plant is now attracting considerable interest as a possible source of pharmaceutically important drugs. Several different classes of compounds such as biflavonoids, benzophenones, benzofurans, benzopyran, vitamin E derivatives, xanthones, and phytosterols, have been isolated from G. kola, of which many appears to be found only in this species, such as garcinianin (found in seeds and roots), kolanone (fruit pulp, seeds, roots), gakolanone (stem bark), garcinoic acid, garcinal (both in seeds), garcifuran A and B, and garcipyran (all in roots). They showed a wide range of pharmacological activities (e.g. analgesic, anticancer, antidiabetic, anti-inflammatory, antimalarial, antimicrobial, hepatoprotective and neuroprotective effects), though this has only been confirmed in animal models. Kolaviron is the most studied compound and is perceived by many studies as the active principle of G. kola. However, its research is associated with significant flaws (e.g. too high doses tested, inappropriate positive control). Garcinol has been tested under better conditions and is perhaps showing more promising results and should attract deeper research interest (especially in the area of anticancer, antimicrobial, and neuroprotective activity). Human clinical trials and mechanism-of-action studies must be carried out to verify whether any of the compounds present in G. kola may be used as a lead in the drug development.

Garcinol protects SH-SY5Y cells against MPP+-induced cell death by activating DJ-1/SIRT1 and PGC-1α mediated antioxidant pathway in sequential stimulation of p-AMPK mediated autophagy

Parkinson's disease (PD), a chronic and progressive neurodegenerative disease, can reduce the population of dopaminergic neurons in the substantia nigra. The cause of this neuronal death remains unclear. 1-Methyl-4-phenylpyridinium ion (MPP+) is a potent neurotoxin that can destroy dopaminergic (DA) neurons and promote PD. Garcinol, a polyisoprenylated benzophenone derivative, was extracted from Garcinia indica and is an important active compound it has been used as an anticancer, antioxidant, and anti-inflammatory, agent and it can suppress reactive oxygen species (ROS) mediated cell death in a PD model. Human neuroblastoma (SH-SY5Y) cells (1 × 10⁵  cells) were treated with MPP+ (1 mM) for 24 h to induce cellular ROS production. The formation of ROS was suppressed by pretreatment with different concentrations of garcinol (0.5 and 1.0 μM) for 3 h in SH-SY5Y cells. The present study found that MPP+ treatment increased the formation of reactive oxygen species (ROS), and the increased ROS began to promote cell death in SH-SY5Y cells. However, our natural compound garcinol effectively blocked MPP+-mediated ROS formation by activating the DJ-1/SIRT1 and PGC-1α mediated antioxidant pathway. Further findings indicate that the activated SIRT1 can also regulate p-AMPK-mediated autophagy to protect the neurons from the damage it concludes that garcinol sub-sequential regulates intracellular autophagy in this model, and the productive efficacy of garcinol was confirmed by western blot analysis and MitoSOX DCFDA and MTT assays. The results showed garcinol increased protection due to the prevention of MPP+-induced ROS and the promotion of cell survival.

Nutrigenomics in Parkinson's disease: diversity of modulatory actions of polyphenols on epigenetic effects induced by toxins

Although the pathogenesis of Parkinson's Disease (PD) is not completely understood, there is a consensus that it can be caused by multifactorial mechanisms involving genetic susceptibility, epigenetic modifications induced by toxins and mitochondrial dysfunction. In the past 20 years, great efforts have been made in order to clarify molecular mechanisms that are risk factors for this disease, as well as to identify bioactive agents for prevention and slowing down of its progression. Nutraceutical products have received substantial interest due to their nutritional, safe and therapeutic effects on several chronic diseases. The aim of this review was to gather the main evidence of the epigenetic mechanisms involved in the neuroprotective effects of phenolic compounds currently under investigation for the treatment of toxin-induced PD. These studies confirm that the neuroprotective actions of polyphenols involve complex epigenetic modulations, demonstrating that the intake of these natural compounds can be a promising, low-cost, pharmacogenomic strategy against the development of PD.

Unveiling the biopathway for the design of novel COMT inhibitors

Catechol-O-methyltransferase (COMT) is an enzyme responsible for the O-methylation of biologically active catechol-based molecules. It has been associated with several neurological disorders, especially Parkinson's disease (PD), because of its involvement in catecholamine metabolism, and has been considered an important therapeutic target for central nervous system disorders. In this review, we summarize the biophysical, structural, and therapeutical relevance of COMT; the medicinal chemistry behind the development of COMT inhibitors and the application of computer-aided design to support the design of novel molecules; current methodologies for the biosynthesis, isolation, and purification of COMT; and revise existing bioanalytical approaches for the assessment of enzymatic activity in several biological matrices.

An insight into therapeutic efficacy of heterocycles as histone modifying enzyme inhibitors that targets cancer epigenetic pathways

Histone modifying enzymes are the key regulators involved in the post-translational modification of histone and non-histone. These enzymes are responsible for the epigenetic control of cellular functions. However, deregulation of the activity of these enzymes results in uncontrolled disorders such as cancer and inflammatory and neurological diseases. The study includes histone acetyltransferases, deacetylases, methyl transferases, demethylases, DNA methyl transferases, and their potent inhibitors which are in a clinical trial and used as medicinal drugs. The present review covers the heterocycles as target-specific inhibitors of histone-modifying enzyme, more specifically histone acetyltransferases. This review also confers more recent reports on heterocycles as potential HAT inhibitors covered from 2016-2022 and future perspectives of these heterocycles in epigenetic therapy.

Discovery of Small Molecules as Membrane-Bound Catechol-O-methyltransferase Inhibitors with Interest in Parkinson's Disease: Pharmacophore Modeling, Molecular Docking and In Vitro Experimental Validation Studies

A pharmacophore-based virtual screening methodology was used to discover new catechol-O-methyltransferase (COMT) inhibitors with interest in Parkinson’s disease therapy. To do so, pharmacophore models were constructed using the structure of known inhibitors and then they were used in a screening in the ZINCPharmer database to discover hit molecules with the desired structural moieties and drug-likeness properties. Following this, the 50 best ranked molecules were submitted to molecular docking to better understand their atomic interactions and binding poses with the COMT (PDB#6I3C) active site. Additionally, the hits’ ADMET properties were also studied to improve the obtained results and to select the most promising compounds to advance for in-vitro studies. Then, the 10 compounds selected were purchased and studied regarding their in-vitro inhibitory potency on human recombinant membrane-bound COMT (MBCOMT), as well as their cytotoxicity in rat dopaminergic cells (N27) and human dermal fibroblasts (NHDF). Of these, the compound ZIN27985035 displayed the best results: For MBCOMT inhibition an IC₅₀ of 17.6 nM was determined, and low cytotoxicity was observed in both cell lines (61.26 and 40.32 μM, respectively). Therefore, the promising results obtained, combined with the structure similarity with commercial COMT inhibitors, can allow for the future development of a potential new Parkinson’s disease drug candidate with improved properties.

Pharmacological Activity of Garcinia indica (Kokum): An Updated Review

Garcinia indica (commonly known as kokum), belonging to the Clusiaceae family (mangosteen family), is a tropical evergreen tree distributed in certain regions of India. It has been used in culinary and industrial applications for a variety of purposes, including acidulant in curries, pickles, health drinks, wine, and butter. In particular, G. indica has been used in traditional medicine to treat inflammation, dermatitis, and diarrhea, and to promote digestion. According to several studies, various phytochemicals such as garcinol, hydroxycitric acid (HCA), cyanidin-3-sambubioside, and cyanidin-3-glucoside were isolated from G. indica, and their pharmacological activities were published. This review highlights recent updates on the various pharmacological activities of G. indica. These studies reported that G. indica has antioxidant, anti-obesity, anti-arthritic, anti-inflammatory, antibacterial, hepatoprotective, cardioprotective, antidepressant and anxiolytic effects both in vitro and in vivo. These findings, together with previously published reports of pharmacological activity of various components isolated from G. indica, suggest its potential as a promising therapeutic agent to prevent various diseases.

Garcinol blocks motor behavioural deficits by providing dopaminergic neuroprotection in MPTP mouse model of Parkinson's disease: involvement of anti-inflammatory response

Although the etiology of Parkinson's disease (PD) is poorly understood, studies in animal models revealed loss of dopamine and the dopaminergic neurons harbouring the neurotransmitter to be the principal cause behind this neuro-motor disorder. Neuroinflammation with glial cell activation is suggested to play a significant role in dopaminergic neurodegeneration. Several biomolecules have been reported to confer dopaminergic neuroprotection in different animal models of PD, owing to their anti-inflammatory potentials. Garcinol is a tri-isoprenylated benzophenone isolated from Garcinia sp. and accumulating evidences suggest that this molecule could provide neuroprotection by modulating oxidative stress and inflammation. However, direct evidence of dopaminergic neuroprotection by garcinol in the pre-clinical model of PD is not yet reported. The present study aims to investigate whether administration of garcinol in the MPTP mouse model of PD may ameliorate the cardinal motor behavioural deficits and prevent the loss of dopaminergic neurons. As expected, garcinol blocked the parkinsonian motor behavioural deficits which include akinesia, catalepsy, and rearing anomalies in the mice model. Most importantly, the degeneration of dopaminergic cell bodies in the substantia nigra region was significantly prevented by garcinol. Furthermore, garcinol reduced the inflammatory marker, glial fibrillary acidic protein, in the substantia nigra region. Since glial hyperactivation-mediated inflammation is inevitably associated with the loss of dopaminergic neurons, our study suggests the anti-inflammatory role of garcinol in facilitating dopaminergic neuroprotection in PD mice. Hence, in the light of the present study, it is suggested that garcinol is an effective anti-parkinsonian agent to block motor behavioural deficits and dopaminergic neurodegeneration in PD.

The Positive Role and Mechanism of Herbal Medicine in Parkinson's Disease

Parkinson's disease (PD) is a complex neurodegenerative disease, manifested by the progressive functional impairment of the midbrain nigral dopaminergic neurons. Due to the unclear underlying pathogenesis, disease-modifying drugs for PD remain elusive. In Asia, such as in China and India, herbal medicines have been used in the treatment of neurodegenerative disease for thousands of years, which recently attracted considerable attention because of the development of curative drugs for PD. In this review, we first summarized the pathogenic factors of PD including protein aggregation, mitochondrial dysfunction, ion accumulation, neuroinflammation, and oxidative stress, and the related recent advances. Secondly, we summarized 32 Chinese herbal medicines (belonging to 24 genera, such as Acanthopanax, Alpinia, and Astragalus), 22 Chinese traditional herbal formulations, and 3 Indian herbal medicines, of which the ethanol/water extraction or main bioactive compounds have been extensively investigated on PD models both in vitro and in vivo. We elaborately provided pictures of the representative herbs and the structural formula of the bioactive components (such as leutheroside B and astragaloside IV) of the herbal medicines. Also, we specified the potential targets of the bioactive compounds or extractions of herbs in view of the signaling pathways such as PI3K, NF-κB, and AMPK which are implicated in oxidative and inflammatory stress in neurons. We consider that this knowledge of herbal medicines or their bioactive components can be favorable for the development of disease-modifying drugs for PD.

Histone Deacetylases Regulation by δ-Opioids in Human Optic Nerve Head Astrocytes

Purpose

We determined whether δ-opioid receptor agonist (SNC-121) regulates acetylation homeostasis via controlling histone deacetylases (HDACs) activity and expression in optic nerve head (ONH) astrocytes.

Methods

ONH astrocytes were treated with SNC-121 (1 µM) for 24 hours. The HDAC activity was measured using HDAC-specific fluorophore-conjugated synthetic substrates, Boc-Lys(Ac)-AMC and (Boc-Lys(Tfa)-AMC). Protein and mRNA expression of each HDAC was determined by Western blotting and quantitative real-time PCR. IOP in rats was elevated by injecting 2.0 M hypertonic saline into the limbal veins.

Results

Delta opioid receptor agonist, SNC-121 (1 µM), treatment increased acetylation of histone H3, H2B, and H4 by 128 ± 3%, 45 ± 1%, and 68 ± 2%, respectively. The addition of Garcinol, a histone-acetyltransferase inhibitor, fully blocked SNC-121–induced histone H3 acetylation. SNC-121 reduced the activities of class I and IIb HDACs activities significantly (17 ± 3%) and this decrease in HDACs activities was fully blocked by a selective δ-opioid receptors antagonist, naltrindole. SNC-121 also decrease the mRNA expression of HDAC-3 and HDAC-6 by 19% and 18%, respectively. Furthermore, protein expression of HDAC 1, 2, 3, and 6 was significantly (P < 0.05) decreased by SNC-121 treatment. SNC-121 treatment also reduced lipopolysaccharide-induced TNF-α production from ONH astrocytes and glial fibrillary acidic protein immunostaining in the optic nerve of ocular hypertensive animals.

Conclusions

We provided evidence that δ-opioid receptor agonist activation increased histone acetylation, decrease HDACs class I and class IIb activities, mRNA, and protein expression, lipopolysaccharide-induced TNF-α production in ONH astrocytes. Our data also demonstrate that SNC-121 treatment decrease glial fibrillary acidic protein immunostaining in the optic nerves of animals with ocular hypertension.

In Vivo Screening of Xanthones from Garcinia oligantha Identified Oliganthin H as a Novel Natural Inhibitor of Convulsions

Epilepsy is a chronic neurological disorder, characterized by recurrent, spontaneous, and transient seizures, and affects more than 70 million people worldwide. Although two dozen antiepileptic drugs (AEDs) are approved and available in the market, seizures remain poorly controlled in one-third of epileptic patients who are suffering from drug resistance or various adverse effects. Recently, the xanthone skeleton has been regarded as an attractive scaffold for the discovery and development of emerging anticonvulsants. We had isolated several dihydroxanthone derivatives previously, including oliganthin H, oliganthin I, and oliganthin N, whose structures were similar and delicately elucidated by spectrum analysis or X-ray crystallographic data, from extracts of leaves of Garcinia oligantha. These xanthone analogues were evaluated for anticonvulsant activity, and a novel xanthone, oliganthin H, has been identified as a sound and effective natural inhibitor of convulsions in zebrafish in vivo. A preliminary structure-activity relationship analysis on the relationship between structures of the xanthone analogues and their activities was also conducted. Oliganthin H significantly suppressed convulsant behavior and reduced to about 25% and 50% of PTZ-induced activity, in 12.5 and 25 μM treatment groups (P < 0.01 and 0.001), respectively. Meanwhile, it reduced seizure activity, velocity, seizure duration, and number of bursts in zebrafish larvae (P < 0.05). Pretreatment of oliganthin H significantly restored aberrant induction of gene expressions including npas4a, c-fos, pyya, and bdnf, as well as gabra1, gad1, glsa, and glula, upon PTZ treatment. In addition, in silico analysis revealed the stability of the oliganthin H-GABAA receptor complex and their detailed binding pattern. Therefore, direct interactions with the GABAA receptor and involvement of downstream GABA-glutamate pathways were possible mechanisms of the anticonvulsant action of oliganthin H. Our findings present the anticonvulsant activity of oliganthin H, provide a novel scaffold for further modifications, and highlight the xanthone skeleton as an attractive and reliable resource for the development of emerging AEDs.

Imbalance of Lysine Acetylation Contributes to the Pathogenesis of Parkinson's Disease

Parkinson’s disease (PD) is one of the most common neurodegenerative disorders. The neuropathological features of PD are selective and progressive loss of dopaminergic neurons in the substantia nigra pars compacta, deficiencies in striatal dopamine levels, and the presence of intracellular Lewy bodies. Interactions among aging and genetic and environmental factors are considered to underlie the common etiology of PD, which involves multiple changes in cellular processes. Recent studies suggest that changes in lysine acetylation and deacetylation of many proteins, including histones and nonhistone proteins, might be tightly associated with PD pathogenesis. Here, we summarize the changes in lysine acetylation of both histones and nonhistone proteins, as well as the related lysine acetyltransferases (KATs) and lysine deacetylases (KDACs), in PD patients and various PD models. We discuss the potential roles and underlying mechanisms of these changes in PD and highlight that restoring the balance of lysine acetylation/deacetylation of histones and nonhistone proteins is critical for PD treatment. Finally, we discuss the advantages and disadvantages of different KAT/KDAC inhibitors or activators in the treatment of PD models and emphasize that SIRT1 and SIRT3 activators and SIRT2 inhibitors are the most promising effective therapeutics for PD.

Bicyclic polyprenylated acylphloroglucinols and their derivatives: structural modification, structure-activity relationship, biological activity and mechanism of action

Bicyclic polyprenylated acylphloroglucinols (BPAPs), the principal bioactive benzophenone products isolated from plants of genera Garcinia and Hypericum, have attracted noticeable attention from the synthetic and biological communities due to their fascinating chemical structures and promising biological activities. However, the potential drug interaction, undesired physiochemical properties and toxicity have limited their potential use and development. In the last decade, pharmaceutical research on the structural modifications, structure-activity relationships (SARs) and mechanisms of action of BPAPs has been greatly developed to overcome the challenges. A comprehensive review of these scientific literature is extremely needed to give an overview of the rapidly emerging area and facilitate research related to BPAPs. This review, containing over 226 references, covers the progress made in the chemical synthesis-based structure modifications, SARs and the mechanism of action of BPAPs in vivo and vitro. The most relevant articles will focus on the discovery of lead compounds via synthetic modifications and the important BPAPs for which the direct targets have been deciphered. From this review, several key points of the SARs and mode of actions of this novel class of compounds have been summarized. The perspective and future direction of the research on BPAPs are concluded. This review would be helpful to get a better grasp of medicinal research of BPAPs and become a compelling guide for chemists dedicated to the synthesis of these compounds.

Garcinol pacifies acrylamide induced cognitive impairments, neuroinflammation and neuronal apoptosis by modulating GSK signaling and activation of pCREB by regulating cathepsin B in the brain of zebrafish larvae

The presence of acrylamide (ACR) in food results in evident cognitive decline, accumulation of misfolded proteins, neurotoxicity, neuroinflammation, and neuronal apoptosis leading to progressive neurodegeneration. Here, we used 4 dpf zebrafish larvae exposed to ACR (1mM/3days) as our model, and neuronal proteins were analyzed. Next, we tested the effect of garcinol (GAR), a natural histone-acetylation inhibitor, whose neuroprotection mechanism of action remains to be fully elucidated. Our result revealed that ACR exposure significantly impaired cognitive behavior, downregulated oxidative repair machinery, and enhanced microglia-induced neuronal apoptosis. Moreover, ACR mediated cathepsin-B (CAT-B) translocation acted as the intracellular secretase for the processing of amyloid precursor protein (APP) and served as an additional risk factor for tau hyper-phosphorylation. Here, GAR suppresses ACR mediated CATB translocation as similar with standard inhibitor CA-074. And, this pharmacological repression helped in inhibiting amyloidogenic APP processing and downstream tau hyper-phosphorylation. GAR neuroprotection was accompanied by CREB, ATF1, and BDNF activation promoting neuronal survival. At the same time, GAR subdued cdk5 and GSK3β, the link between APP processing and tau hyper-phosphorylation. Taken together, our findings indicate that GAR rescued from ACR mediated behavioral defects, oxidative injury, neuroinflammation, undesirable APP processing, tau hyper-phosphorylation which in turn found to be CATB dependent.

An Update of Palmitoylethanolamide and Luteolin Effects in Preclinical and Clinical Studies of Neuroinflammatory Events

The inflammation process represents of a dynamic series of phenomena that manifest themselves with an intense vascular reaction. Neuroinflammation is a reply from the central nervous system (CNS) and the peripheral nervous system (PNS) to a changed homeostasis. There are two cell systems that mediate this process: the glia of the CNS and the lymphocites, monocytes, and macrophages of the hematopoietic system. In both the peripheral and central nervous systems, neuroinflammation plays an important role in the pathogenesis of neurodegenerative diseases, such as Parkinson’s and Alzheimer’s diseases, and in neuropsychiatric illnesses, such as depression and autism spectrum disorders. The resolution of neuroinflammation is a process that allows for inflamed tissues to return to homeostasis. In this process the important players are represented by lipid mediators. Among the naturally occurring lipid signaling molecules, a prominent role is played by the N-acylethanolamines, namely N-arachidonoylethanolamine and its congener N-palmitoylethanolamine, which is also named palmitoylethanolamide or PEA. PEA possesses a powerful neuroprotective and anti-inflammatory power but has no antioxidant effects per se. For this reason, its co-ultramicronization with the flavonoid luteolin is more efficacious than either molecule alone. Inhibiting or modulating the enzymatic breakdown of PEA represents a complementary therapeutic approach to treating neuroinflammation. The aim of this review is to discuss the role of ultramicronized PEA and co-ultramicronized PEA with luteolin in several neurological diseases using preclinical and clinical approaches.

Inflammaging and Oxidative Stress in Human Diseases: From Molecular Mechanisms to Novel Treatments

It has been proposed that a chronic state of inflammation correlated with aging known as inflammaging, is implicated in multiple disease states commonly observed in the elderly population. Inflammaging is associated with over-abundance of reactive oxygen species in the cell, which can lead to oxidation and damage of cellular components, increased inflammation, and activation of cell death pathways. This review focuses on inflammaging and its contribution to various age-related diseases such as cardiovascular disease, cancer, neurodegenerative diseases, chronic obstructive pulmonary disease, diabetes, and rheumatoid arthritis. Recently published mechanistic details of the roles of reactive oxygen species in inflammaging and various diseases will also be discussed. Advancements in potential treatments to ameliorate inflammaging, oxidative stress, and consequently, reduce the morbidity of multiple disease states will be explored.

An in silico investigation on the inhibitory potential of the constituents of Pomegranate juice on antioxidant defense mechanism: Relevance to neurodegenerative diseases

Elevation in the levels of reactive oxygen and nitrogen species (RONS), and downregulation of cellular antixoidants, have ubiquitously been reported from studies in animal models of neurodegenerative diseases, including Parkinson’s disease (PD) and Alzheimer’s disease (AD). Thus, plant-derived compounds are widely being investigated for their beneficial effects in these models. However, while studies have reported antioxidant potentials of several phytochemicals, a large number of studies have demonstrated different phytochemicals to be rather pro-oxidant and exaggerate oxidative stress (OS). One such study aimed to investigate possible ameliorative effect of Pomegranate juice (PJ) in rat model of toxin-induced parkinsonism revealed that PJ exacerbates OS, inflammation and promotes neurodegeneration. Thus, it remains to be investigated whether different constituents and metabolites of PJ are pro-oxidant or anti-oxidant. Using computational modeling, we investigated possible inhibitory potential of different constituents of PJ and their metabolites viz. delphinidin-3-glucoside, dimethylellagic acid-glucuronide, ellagic acid, ellagitannin, gallic acid, gallotannin 23, pelargonidin, punicalagin, urolithin A, urolithin A-glucuronide and urolithin B, on anti-oxidant defense system of the brain. The results indicate that the constituents of PJ have the potential to inhibit five key enzymes of the neuronal antioxidant defense system, viz. catalase, superoxide dismutase, glutathione peroxidase 4, glutathione reductase and glutathione-S-transferase. Thus, it is surmised that the constituents of PJ may contribute to OS and neurodegeneration by way of affecting antioxidant defense mechanism. This may particularly be more pronounced in neurodegenerative diseases, since neurons are known to be more vulnerable to OS. Thus, the present findings caution the use of PJ in patients prone to OS, especially those suffering from neurodegenerative diseases, and warrant further experimental studies to unveil the effects of individual components and metabolites of PJ on antioxidant defense system of brain.